Freeze-fracture replication of junctional complexes in unincubated and incubated chick embryos

  title={Freeze-fracture replication of junctional complexes in unincubated and incubated chick embryos},
  author={Ruth Bellairs and A. S. Breathnach and M. Gross},
  journal={Cell and Tissue Research},
SummaryJunctional complexes have been investigated in the epiblast of young chick embryos by examination of freeze-fracture replicas and of sections of comparable specimens stained with lanthanum nitrate. By means of freeze-fracture, tight junctions were shown to be present in the unincubated embryo (stage 1 of Hamburger and Hamilton). The number of ridges or grooves was found to vary between 2 and 10 near the dorsal border, whereas isolated ridges were found more ventrally. Lanthanum was… 

Cell junctions in explanted tissues from early chick embryos

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Mechanisms, mechanics and function of epithelial–mesenchymal transitions in early development

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Strong electrical currents leave the primitive streak of chick embryos.

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Junctional complexes in the preimplantation rabbit embryo

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Intercellular contact in the unincubated chick embryo

  • E. Sanders
  • Biology
    Zeitschrift für Zellforschung und Mikroskopische Anatomie
  • 2004
SummaryThe unincubated chick blastoderm, which consists of a complete upper epithelial layer of one cell thickness (epiblast) and an incomplete lower layer (hypoblast), was examined with the electron


The assembly process in both apical and basal regions conforms with the concept of translational movement of particles within a fluid plasma membrane.

Further observations on the fine structure of freeze-cleaved tight junctions.

Evidence is presented suggesting that fragments of tight junctions can be internalized and broken down in lysosome-like vesicles.


The fine structure and distribution of tight and gap junctions in epithelia of the rat pancreas, liver, adrenal cortex, epididymis, and duodenum, and in smooth muscle were examined in paraformaldehyde-glutaraldehyde-fixed, tracer-permeated, and freeze-fractured tissue preparations.


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Gap junctions between electrotonically coupled cells in tissue culture and in brown fat.

An electron microscopic study of replicas of frozen-fractured BHK21 cells and brown fat cells of newborn mice indicates that gap junctions, when they are the only intercellular junctions present, are sufficient to account for electronic coupling between cells.